My pool recently had an invasion of Yellow algae. Killed this off with a copper based algae killer and a flocking agent.
In order for the flocking agent to work properly I was told to raise my pH to high normal to just above high normal. I applied the flocking agent and waited. 2 days later, the water was still milky white. I took in a water sample. ph was mid normal but the Alkalinity was 40. So they told me to raise my alkalinity using baking soda. (this is what I usually use so I didn't question it. ) Using the Px'd 30 lb's of baking soda on retest my alkalinity was 160. Ph almost 8. The water remains milky/ cloudy. I have vacuumed to waste 2x now, and run the filter for 24 hrs after this. The water is unchanging.
Please let me note that at the start of the season the water was a little cloudy post shocking and flocking to kill and clear the algae. Dropping the pH cleared this as I discovered that Calcium makes the water cloudy when the pH is high. My Ca by the way is about 550. And I can't find anyone in the area who sells the ONLY chemical which removes Ca from the water, Cal treat.
I am draining and having the pool resurfaced this fall but in the meantime I would love the water to be clear again.